50 lines
1.2 KiB
Markdown
50 lines
1.2 KiB
Markdown
# Ethereum primitives
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[](https://travis-ci.org/paritytech/primitives)
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Fixed-sized integer arithmetic (ethereum-types) and bloom filter (ethbloom)
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To add this crate to your project, add the following in `Cargo.toml`
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```toml
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[dependencies]
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ethereum-types = "0.4"
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ethbloom = "0.5"
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```
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A basic example how to use this crate:
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```rust
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extern crate ethereum_types;
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extern crate ethbloom;
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use ethereum_types::U256;
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use ethbloom::{Bloom, Input};
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fn main() {
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let mut val: U256 = 1023.into();
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for _ in 0..200 { val = val * 2u32 }
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assert_eq!(
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&format!("{}", val),
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"1643897619276947051879427220465009342380213662639797070513307648"
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);
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let address = [0_u8; 32];
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let mut my_bloom = Bloom::default();
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assert!(!my_bloom.contains_input(Input::Raw(&address)));
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my_bloom.accrue(Input::Raw(&address));
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}
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```
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### `no_std` crates
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This crate has a feature, `std`, that is enabled by default. To use this crate
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in a `no_std` context, add the following to your `Cargo.toml`:
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```toml
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[dependencies]
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ethereum-types = { version = "0.4", default-features = false }
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ethbloom = { version = "0.5", default-features = false }
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```
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